I have a Samsung T301g. SIM# 8901260732138673318 Serial # 011844000886091. Tracfone is my provider. I have a problem with service Every time I go out of Scranton or into a building, the display has the signal bars in the upper left corner, but it also displays a phone with a line through it right next to the signal bars and the phone doesn't work. I travel out of Scranton a lot--Moscow, Tobyhanna, Olyphant, etc. so this is a big problem for me. What causes this and what can I do to fix it? Is there a way I can enhance the signal?